The biggest losers (and winners) from US trade liberalization

Many development experts worry that continuing reductions of tariff levels in high-income countries will limit trade flows from developing countries that benefit from preferential trade programs because of 'preference erosion.' Using a panel of US import data between the years of 1997 and 2005, I find that reductions in preference margins will significantly diminish imports of some products, particularly from lower-middle and low income countries; for example, a 1% reduction in the US tariff on a product that is currently imported duty-free from developing countries will decrease imports of that product from lower-middle income countries by an average of 2.6%. However, many products produced by developing countries fail to qualify for preferential tariffs, thus a gradual reduction in all US tariff rates is expected to have only a modest impact on trade flows from developing countries.